Printing-press.



M. J. BULGER.

PRINTING PRESS.

APPLICATION FILED DEG.11, 1909 1, 1 21,896. Patnted. Dec. 22, 1914.

H1: NORRIS PETERS COH'FHOTCFLITHD. WASHINGTON, D. r

MATTHEW J. BULGER, OF NEW YORK, N.

PRINTING-PRESS.

Specification of Letters Patent.

Patented Dec. 22 1914.

Application filed December 11, 1909. Serial No. 532,540.

To all whom it may concern Be it known that I, MATTHEW J. Bureau,

'a citizen of the United States, residing at New York city, New York, have invented certain new and useful Improvements in Printing-Presses, of which the following is a clear, full, and exact description.

My invention relates to an improvement in printing presses whereby a resilient contact is obtained between the impression member and the printing plate, with resulting advantages which I shall hereafter describe.

My invention will be more particularly described in the following specification and the scope thereof set forth in the appended claim.

In the drawings which represent a preferred form of my invention, Figure 1 is a plan view of a printing plate detached. Fig. 2 is a section of the printing plate detached, through line X-X of Fig. 1. Fig. 3 is a section detail of a cylinder press to show the cooperation between the impression cylinder and the plate.

Referring to the drawings, Figs. 1 and 2 indicate one preferred method in which a cushion is carried by the printing block. 1 indicates the body portion of my preferred plate, which may be of wood or other suitable material, and surrounding this body 1 on all sides are metallic side pieces 2. These side pieces project slightly above the surface of the body portion to form a projecting rim or flange 4. Mounted on the block and retained within this rim or flange is a resilient cushion 8 of rubber or other material, which may be preferably made of a thickness at least equal to the height of the rim to form a plane surface over the entire block. Resting on the rubber cushion 8 is a plate 9, which may be the ordinary form of electrotype plate used for printing. This plate is formed with beveled edges 9*, as shown, and is secured to the block by means of suitable clamping devices such as those shown.

These clamping devices comprise a projecting and inwardly-turned flange 5 arising from two of the side pieces having a narrow edge contact therewith, and opposite to each of these flanges are disposed movable clamps 6 which are carried on, and operated by, screw bolts 7 having toothed wheels 7 at their outer ends for turning. It will be evident that the means thus shown for clamping the printing plate in position absolutely secure it against lateral movement while permitting a slight vertical play of the same upon its resilient backing under the force of the impression cylinder. Since the layer of rubber S is confined within the flanged rim 4 of the printing block and cannot spread out at its lateral edges or flatten under the pressure from the impression roller, a much more firm and uniform resiliency is obtained which permits of a much more accurate and easy adjustment of the block forv getting good printing results. Additional side pieces 8 for carrying. these bolts 7 are mounted on two sides of the block as shown.

These side pieces 3, along with the side pieces 2, are all secured to the block by any suitable means, such as bolts 10.

It is obvious that the effect I wish to accomplish by this invention may be obtained by mounting a cushion on the impression cylinder as shown in Fig. 3, but in either case this cushion should be located a very slight distance below the surface or impression point, for the reason that only a slight cushioning effect locally over the surface of the contacting members is necessary to obtain the improved result, and it is desirable to keep the body of said members, both the impression cylinder and plate, in accurately fixed relationship.

Referring to Fig. 3, I have shown a portion of a cylinder press in which 12 indicates the frame, 18 a cylinder having a shaft 15 carried in adjustable bearings 16. Slightly below the surface 14: of the cylinder 13 is mounted the cushion 8 It is understood that the paper to be printed upon passes between the cylinder and plate 1, which plate usually moves back and forth to press against the periphery of the cylinder to print, and therefore since the cylinder is provided with this cushion the same resilient impression is obtained as when the cushion is mounted on the plate.

In the running of a printing press it is of great importance that the entire surface of the printing plates receive exactly the same pressure from the impression cylinder in order to make the printing uniform throughout the page. If faint or unprinted spots are found to exist on a printed page, this must immediately be remedied by raising certain portions of the surface of the cylinder or of the plate. This is usually done by overlaying on the cylinder, that is,

sticking pieces of paper upon the low spots of the cylinder aiidlikewise by 'underlayi'ng or inserting pieces of paper beneath certain spots of the plate. This has been the method heretofore in obtaining a uniform impression upon the printed page, but it is open to the objection that with too much overlaying or underlaying, er the necessity of underlay- 'ent plates. the use of my resilient cushion, h0w ever,'the" bearing may be securely fixed in' a position'to give'a very firm impression, andthe cushioning effect between "theeylind'er and the-plate allows the higher portions to yield. This also obviates the nec essity almost entirely of underlaying the plates since what faint impressions" are still present in'the printing of a sheet may be remedied by overlaying the cylinder if necessary. This of course -greatly facilitates "thesettingupof the press. The cushioning effect "of' the impression cylinder also prevents'the destruction of the plate surface "due'to presence ofchips or articles carelessly dropped into the press, since the surface will "yield sufficiently "to 'allow them to pass through. Also at present in a Web press the 5 'paper -passing'through the first impression 3 V and;p'late'cylinder to-be printed on one side usually receives a'surplus amount of ink "andi'an extraheavy impression, so that when "the sheet passes through the second impression cylinder and plate cylinder to be printed upon the otherside, the off-set roll employed to dry the previously printed side, will leave sui'iicient ink to give a good printed surface. By the use of my cushion either on the plate cylinder or on the impression cylinder, the pressure may be made firmly enough to print the page with a small amount of ink and yet without indenting the sheet sufficient to mutilate it. It is pos sible, thereby, to use less ink on the first impression and still get a good printed surface which quickly dries before it comes to the second impression and plate cylinders,

whereby the offset roll is no longer necess sary.

Vhat I claim is: 'In a printing press in combination, an 1mpression cylinder carried in unyielding bearings and adapted to roll in contact with" the "planesurfaceof'a' printing member mounted in an 'unyleldlng carrier to obtain a fixed relationship between said printing surface and cylmderysaid printing member comprlsin'g a wooden base block, asingleprinting plate of a comparatively thin flexible metal mounted upon said block adapted to flex throughout its entire surface, clamping devicesfor holding'said plate to said block and an intermediate layer'ofrubber between 'said' metal plate and Wooden block for allowing said whole plate to flex as one piece under the pressure of'said impression cylinder. V

Signed at New York city, N. Y.'this 10 day of December, 1909.

v MATTHEW J. BULGER. Witnesses:

BEATRICE MIRvIs,

IDA G1 GILMORE.

ca es of-flnls patent'may be obtained for five cents e'ah, by' addres'sing'the Commissioner of Patents,

' Washington, D; G. 

